This project is studying the measurement of the rates of synthesis and degradation of proteins in human cell lines derived from normal and mutant individuals. Specific enzymes under study are galactose-1- phosphate uridylyltransferase, glucose-6-phosphate dehydrogenase, catalase and beta-galactosidase. In addition interspecific cell hybridization is being used to determine the chromosomal sites of genes responsible for enzymes of galactose metabolism, hexosamindase and mannosidase in man are being determined. Through cell fusion, complementation analysis of the gene or genes responsible for gal-1-P uridylyltransferase is being performed.